Our work at Cissbury Ring

View over Cissbury Ring, Sussex, in summer — View over Cissbury Ring in summer | © National Trust Images/David Sellman

To maintain and improve the land we care for here at Cissbury Ring hillfort, the site of ancient flint mines, we need to control the growth of scrub. We do this with the help of human volunteers and a herd of New Forest ponies. Discover what we’ve achieved so far and the historical features it has revealed.

The flint mines at Cissbury Ring

Cissbury Ring is the site of one of the biggest flint mines on the South Downs and the resulting dips and hollows have become part of its character. As part of our plans for Cissbury Ring, we want to highlight the historical features of this much-loved hillfort – and the flint mines, believed to be Neolithic, are its most obvious internal features.

However, due to the protection these dips give from the weather, invasive plant life – such as scrub, young trees and brambles – can quickly take hold. We therefore regularly remove them.

Earthworks at Cissbury Ring, West Sussex — Earthworks at Cissbury Ring | © National Trust Images/Tim Stephens

Why clear invasive plant life here?

The shrubs and trees that colonise the old flint mines damage the archaeological stratification with their deep roots, and their shade deters sometimes rare wildflowers and mini beasts. They also provide cover for rabbits, and their burrowing activities are a further threat to the archaeological remains.

Removing some of the trees and dense vegetation also helps to create a more accessible and beautiful landscape – and conserve this historic hillfort for generations to come.

Why are some trees fenced in?

You may have noticed a section of fencing enclosing a yew tree and two large pits. This was erected so that the yew tree could be preserved within the grazed area. Yew is poisonous to most grazing stock but provides winter berries for important migrant birds.

In the winter, large flocks of ring ouzels can be seen feeding in the Cissbury area, including on this yew tree, and against the dark winter foliage they can make a spectacular sight.

Chalky path winding along the top of a bank at Cissbury Ring, West Sussex, with a view off over the green fields to the left, with a blue cloudy sky. — Chalky path winding along the top of a bank at Cissbury Ring, West Sussex | © National Trust Images/Tim Stephens

Controlling the vegetation

Where possible we try to avoid intensive human intervention. The most effective and sustainable means of controlling vegetation growth on chalk grassland is by grazing with livestock. At Cissbury Ring, a small herd of New Forest ponies helps us look after this special place.

New Forest ponies

The New Forest pony is an ideal breed to use for conservation and does extremely well on land like we have at Cissbury Ring. The ponies here are relatively low maintenance and are managed as a semi-wild herd. We check them regularly and vets carry out an annual assessment. They are intelligent and resourceful and will also browse hawthorn berries, young trees and thistle buds.

The results of their grazing

The action of their constant grazing and meandering across the hillfort has helped to remove plenty of the old grass ‘thatch’ and knocks back the invasive scrub and bramble that can encroach onto paths and open areas and is now making way for wild flowers, wildlife and walkers. In addition, historic features on the ground are now more visible. The landscape at Cissbury Ring has finally started to return to its true form as chalk grassland – one of the rarest habitats in the UK.

Close-up of a white pony and a dark brown foal grazing — New Forest ponies help to keep the vegetation under control at Cissbury Ring | © National Trust Images/John Miller

Areas where you can see the ponies' impact

The Roman temple

With the action of grazing and our team of volunteers removing the gorse, this historic feature is once more clear to see on the ground. This temple is typical of the archaeological features that will become more prominent as the ponies do their job. Without the grazing, this would have been a constant job for our team.

The inner ramparts

The ponies spread out in a wide group, grazing up the sides of the ramparts rather than walking in a line on the exposed chalk. This is perfect for conservation. Their actions widen the paths and keep them clear so the thousands of people who visit don’t all walk on the same line, which can add to the erosion.

The outer ditches

In winter, when the grass stops growing, our intrepid herd’s grazing has more of an impact in the hard-to-reach outer ditches. Without them, we would have to use specialist equipment and many volunteer hours working on the steep and uneven ground.